Drugmaker Johnson & Johnson has halted production of its single-dose COVID-19 vaccine, according to a New York Times report. The pharmaceutical company last year quietly shut down production at a plant in Leiden, Netherlands, which was the only facility where usable doses of the vaccine were manufactured, catching some of its customers off guard, the report states. Johnson & Johnson has instead been using the plant to work on an experimental and potentially more profitable drug that could protect against an unrelated respiratory virus, according to the report.